Certified GKH Gardening Expert
This is unusual, but serious. It appears to be Tomato Spotted Wilt Virus. Viral infections, like humans, cannot be cured- It can only be treated. This one will take hold of tomatoes peppers, and any other closely related species.
The soil is bad. It should be disposed of, well, away from your property. Should this spread to your outdoor soil, or any other soil that you use, regularly, you will likely face a permanent viral infection in your soil. It won't harm you in any way, but you will never be able to grow any plant in the area that can be infected, should this happen.
The pepper is still edible, but that plant needs to be destroyed, quickly.